As the value and use of information continues to increase, individuals and businesses seek additional ways to process and store information. One option available to users is information handling systems. An information handling system generally processes, compiles, stores, and/or communicates information or data for business, personal, or other purposes thereby allowing users to take advantage of the value of the information. Because technology and information handling needs and requirements vary between different users or applications, information handling systems may also vary regarding what information is handled, how the information is handled, how much information is processed, stored, or communicated, and how quickly and efficiently the information may be processed, stored, or communicated. The variations in information handling systems allow for information handling systems to be general or configured for a specific user or specific use such as financial transaction processing, airline reservations, enterprise data storage, or global communications. In addition, information handling systems may include a variety of hardware and software components that may be configured to process, store, and communicate information and may include one or more computer systems, data storage systems, and networking systems.
A computer system is one type of information handling system. Examples of the computer system include a server, a workstation, a desktop computer, a notebook computer, a laptop computer, and a hand-held device. The computer system, typically, includes a microprocessor, memory, a video display, a keyboard, a mouse, storage devices, media drives and optical drives.
The computer system may also include peripheral devices, such as a keyboard, a mouse, disk drives, that connect to the computer via input/output (I/O) ports. The I/O ports allow the peripheral devices to communicate with the processor and in some cases other devices through a bus such as a peripheral component interconnect (PCI) bus. In general, the bus may include a parallel or a serial interface for connecting the peripheral devices to the computer system.
FIG. 1 is a schematic view of conventional PCI bus architecture system 10 including microprocessor 12 and memory chips 14 connected to chipset 20. Microprocessor 12 may connect to chipset 20 via microprocessor bus 13. Memory chips 14 communicates to chipset 20 via memory chip bus 15. Chipset 20 includes memory hub 22 and I/O hub 24 connected via chipset bus 23. Video card 40 receives graphics data from microprocessor 12 and memory chips 14 through memory hub 22 via video card bus 38. Video card 40 creates the video signal for display on a monitor.
I/O hub 24 connects multiple computer components to microprocessor 12 and memory chips 14. Typically, the I/O hub 24 connects devices in parallel using a different interface for each type of device. For example, I/O hub 24 may include a universal serial bus (“USB”) interface to allow USB devices to connect to I/O hub 24 via USB ports 28e. Similarly, 1394 adapter 30 connects to I/O hub 24 using a PCI interface to permit microprocessor 12 and memory chips 14 to communicate with a 1394 device. Additionally, encode and decode device (“CODEC”) 32, mainly used with audio data, connects to I/O hub 24, which provides a connection for audio components and may also include an interface within I/O hub 24.
Hard disk drive 26 is one type of storage media that may be used with conventional PCI bus architecture system 10. Hard disk drive 26 connects to I/O hub 24 via an interface bus dedicated for storage media information, such as a small computer system interface (“SCSI”) and an integrated device electronics (“IDE”) interface.
PCI cards 34 may connect in parallel to I/O hub 24 via PCI bus 33. PCI cards 34 provide separate connections for allowing a computer component to communicate with microprocessor 12 and memory chips 14 via PCI card ports 35.
As consumer demand faster computer speeds and performance, technological innovations have exceed the capabilities of current bus architectures such as the conventional PCI bus architecture. Technological innovations including high performance graphics, faster memory and microprocessors, networking, and computer devices have created a need for a high performance, greater bandwidth interconnects. In order to meet this need, a new interconnect architecture has been developed to provide high speed, point-to-point interconnect architecture commonly referred to as PCI Express architecture. The specification for the PCI Express architecture is described in the PCI Express Specification 1.0 available through PCI-SIG, which is hereby incorporated by reference in its entirety.
PCI Express architecture is a general purpose input/output (I/O) serial interconnect that provides a highly scalable bandwidth interconnect for attaching devices such as high performance graphics, universal serial bus (USB) ports, networking and other such devices. Because PCI Express architecture may connect to several different types of devices, the architecture provides a unifying standard for communications in order to consolidate these devices on a single interconnect.
System designs for PCI Express architecture, however, provide a separate link for graphics data and data for peripheral devices. Thus, a computer system that uses a PCI Express architecture may use a first link for graphics data and a second link for peripheral data. For example, a printed circuit board such as a motherboard in a computer system may use a first graphics link to interconnect a processor to a graphics controller through a memory hub such that the first graphics link carries only graphics data. A second link, formed on the motherboard, typically carries peripheral data from the processor to computer components.